Mercurial > vim
changeset 33791:370543108ba1 v9.0.2114
patch 9.0.2114: overflow detection not accurate when adding digits
Commit: https://github.com/vim/vim/commit/22cbc8a4e17ce61aa460c451a26e1bff2c3d2af9
Author: Christian Brabandt <cb@256bit.org>
Date: Sun Nov 19 10:47:21 2023 +0100
patch 9.0.2114: overflow detection not accurate when adding digits
Problem: overflow detection not accurate when adding digits
Solution: Use a helper function
Use a helper function to better detect overflows before adding integer
digits to a long or an integer variable respectively. Signal the
overflow to the caller function.
closes: #13539
Signed-off-by: Christian Brabandt <cb@256bit.org>
Signed-off-by: Michael Henry <vim@drmikehenry.com>
Signed-off-by: Ernie Rael <errael@raelity.com>
| author | Christian Brabandt <cb@256bit.org> |
|---|---|
| date | Sun, 19 Nov 2023 11:00:07 +0100 |
| parents | ef49dc24dab1 |
| children | 5100c01a1f1d |
| files | src/misc1.c src/normal.c src/proto/misc1.pro src/version.c |
| diffstat | 4 files changed, 28 insertions(+), 4 deletions(-) [+] |
line wrap: on
line diff
--- a/src/misc1.c +++ b/src/misc1.c @@ -975,9 +975,8 @@ get_number( c = safe_vgetc(); if (VIM_ISDIGIT(c)) { - if (n > INT_MAX / 10) + if (vim_append_digit_int(&n, c - '0') == FAIL) return 0; - n = n * 10 + c - '0'; msg_putchar(c); ++typed; } @@ -2817,3 +2816,25 @@ may_trigger_modechanged(void) restore_v_event(v_event, &save_v_event); #endif } + +// For overflow detection, add a digit safely to an int value. + int +vim_append_digit_int(int *value, int digit) +{ + int x = *value; + if (x > ((INT_MAX - digit) / 10)) + return FAIL; + *value = x * 10 + digit; + return OK; +} + +// For overflow detection, add a digit safely to a long value. + int +vim_append_digit_long(long *value, int digit) +{ + long x = *value; + if (x > ((LONG_MAX - (long)digit) / 10)) + return FAIL; + *value = x * 10 + (long)digit; + return OK; +}
--- a/src/normal.c +++ b/src/normal.c @@ -2563,12 +2563,11 @@ nv_z_get_count(cmdarg_T *cap, int *nchar n /= 10; else if (VIM_ISDIGIT(nchar)) { - if (n > LONG_MAX / 10) + if (vim_append_digit_long(&n, nchar - '0') == FAIL) { clearopbeep(cap->oap); break; } - n = n * 10 + (nchar - '0'); } else if (nchar == CAR) {
--- a/src/proto/misc1.pro +++ b/src/proto/misc1.pro @@ -53,4 +53,6 @@ int path_with_url(char_u *fname); dict_T *get_v_event(save_v_event_T *sve); void restore_v_event(dict_T *v_event, save_v_event_T *sve); void may_trigger_modechanged(void); +int vim_append_digit_int(int *value, int digit); +int vim_append_digit_long(long *value, int digit); /* vim: set ft=c : */